PAP Therapy Devices: Delivering the Right Therapy To The Right Patient Ryan Schmidt, BS, RRT Clinical Specialist Philips Respironics
Conflict of Interest Disclosure(s) I do not have any potential conflicts of interest to disclose, OR X_I wish to disclose the following potential conflicts of interest: Type of Potential Conflict/Details of Potential Conflict Grant/Research Support Consultant Speakers Bureaus Financial support X Other Employee of Philips Respironics Confidential
Objectives Review prevalence, etiology, and impact of sleep disordered breathing (SDB) Review the various forms of therapy available for patients identified with OSA, CSA, and Respiratory Insufficiencies CPAP - Adaptive Servo Ventilation Bi-level therapy - AVAPS/iVAPS Auto-PAP therapy Review and explain the different PAP acronyms from the various manufactures. Determine how to match the patient s disease process to the correct PAP Device
Normal sleep effects on respiration Sleep Decrease muscle tone Increased airway resistance Decrease drive to breath PaCO 2 2 8 mm Hg PaO 2 3 10 mm Hg
Sleep Architecture REM REM REM REM REM Awake N1 N2 N3 0 1 2 3 4 5 6 7 Hours of sleep
Prevalence of Sleep Disordered Breathing 5% of population is estimated to have undiagnosed OSA 1 As common as adult asthma 1 Obstructive Sleep Apnea/hypopnea (OSA/H) prevalence: Wisconsin study 2,3 : 24% of men, 9% of women: apnea/hypopnea Index (AHI) > 5 9% of men, 4% of women: AHI >15 4% of middle-aged men, 2% of middle-aged women: AHI > 5 and daytime sleepiness Pennsylvania study 4 : 17% of men AHI >5 7% of men, 2% of women: AHI >15 1 Young, et al., AJRCCM 2002 2 Young, et al., NEJM 1993 3 Redline, et al., AJRCCM 1997 4 Bixler, et al., AJRCCM 1998 & 2001
Obstructive Sleep Apnea (OSA) Closed airway Open Airway Central Sleep Apnea (CSA) -Cessation of inspiratory flow > 10 seconds often associated with a substantial O 2 desaturation. -Severity measured as an Apnea Hypopnea Index per hour of sleep (i.e. AHI= 40) -Hypopnea= 30% reduction in flow with a 3-4% desaturation followed by an arousal Open airway -Cessation of inspiratory flow > 10 seconds with no respiratory effort -CSA results from complete withdrawal of central respiratory drive to the muscles of respiration during sleep
Sleep Apnea Terms You May Hear Apnea Index # apneas per hour of sleep # of obstructive apneas per hour of sleep # of central apnea s per hour of sleep Hypopnea Index # of reduction in patient flow per hour of sleep associated with a desaturation and arousal from sleep # of central or obstructive hypopnea s per hour of sleep Apnea / Hypopnea Index (AHI) # apneas + hypopneas per hour of sleep Arousal Index (AI) When the patient arouses from sleep or changes sleep staging that does not normally occur at night Number of arousals in EEG activity per hour of sleep Associated with apnea/hypopnea/desaturation events Associated with other events (PLM, seizure, etc)
Pathologic Breathing Cycle of OSA Wakefulness Sleep Airway Patency Compensation Arousal & Hyperventilation O 2 & CO 2 Increased RR Increased mental activity Increased BP Increased HR Increased release of glucose Decreased Compensation Airway Collapse O 2 & CO 2 Sympathetic Activation
Pathologic breathing cycle of OSA Wakefulness Airway patency Compensation Sleep Hyperventilation CO 2 / O 2 Decreased compensation Arousal/sleep fragmentation Airway collapse Hypoxia/hypercapnia Increased effort Sympathetic activation
Prevalence of sleep disordered breathing in cardiovascular disease 30%-50% of hypertensive patients 83% of refractory hypertension Logan et al, J Hypertension 2001 50% of heart failure patients Javaheri, Circulation 1998 40% pts with systolic HF 50% pts with diastolic HF 30% of cardiac disease patients Schafer et al, Cardiology 1999
Health consequences of untreated OSA Short Term Automotive accidents Excessive sleepiness Neurocognitive and performance deficits Decreased quality of life Long Term Hypertension Heart disease Heart attack Arrhythmias Stroke Impaired glucose tolerance Depression
Sleep Disordered Breathing: Patient Types Sleep Disordered Breathing Obstructive Sleep Apnea 80 90% of patients Apnea/Hypopnea Index (AHI) controlled by PAP therapy Central Sleep Apnea Idiopathic Central Sleep Apnea Brain issue with control of respiration Periodic breathing Heart failure vs. non heart failure populations Chemoreceptor issue/co 2 issue Pain management patients Complex Sleep Apnea CPAP Emergent events Chemoreceptor issue Hypoventilation Disorders May/May Not have SDB Obstructive Disorders COPD Pulmonary Fibrosis Restrictive Disorders Neuromuscular disease Amyotrophic Lateral Sclerosis (ALS) Guillain-Barre (GB) and Myasthenia Gravis (MG) Obesity hypoventilation Chest wall deformities kyphosis/scoliosis All forms lead to hypoventilation of the lung regions and atelectasis
Proper PAP Treatment Should Target the Particular Disease Process
First Step: Understanding the Alphabet Soup CPAP Auto CPAP Auto PAP BiPAP VPAP Auto VPAP Auto BiPAP Adapt SV Auto SV AVAPS ivaps
Gold Standard for OSA: CPAP therapy Lower incidence of hypertension Lower incidence of cardiovascular disease Lower incidence of stroke Increased control of diabetes
OSA therapy CPAP (Continuous Positive Airway Pressure) act as a pneumatic splint for the patient s airway Measured in Cm H2O One pressure used to treat all events Apneas, Hypopneas, Flow Limitations Comfort features such as Flex/EPR, humidification, and ramp may be available to aid in compliance Used in Both Adult and Pediatric Patients Of those patients being treated, 80% utilize CPAP with a nasal mask/pillows for treatment 1 1 Frost & Sullivan, Sleep Apnea Models, 2001
Goals of treating OSA with PAP Short term Maintain open airway Improve quality of sleep Alleviate daytime symptoms Sleepiness Moodiness/Impaired concentration/memory loss Morning headache Long term Reduce mortality and morbidity Decrease cardiovascular consequences Reduce sleepiness Improve quality of life Marin, JM et. al Lancet 2005: 365:1046-1053
Auto PAP Therapy Auto CPAP
Implementation of Auto Therapy Auto CPAP Device pressure is adjusted based on airway dynamics and device algorithm Algorithms vary by manufacturer Auto CPAP Indications: Unstable pressure needs Difficult initial titration Failure of PAP therapy in the home REM or Positional OSA Verify CPAP pressure is therapeutic Weight changes First line of therapy for some Home Based Studies Prescription written as a range of pressure: Example: Min EPAP 4 Max EPAP 20
Auto CPAP algorithm Primary Function Proactive Analysis Safety net Vibratory snore RERA Leak tolerance Hypopnea Obstructed airway apnea Complex patient check #1 Goal: normalize sleep #2 Goal: minimize pressure Clear airway apnea Periodic breathing 21
Bi-Level Therapy
What is BiPAP/Bi-Level Therapy? Bi-level devices have two independently adjusted pressures that are set by the clinician. May be used for Sleep Disorders OR Ventilation Support IPAP (inspiratory positive airway pressure) Always the higher number Increases lung volume and decreases work of breathing Pressure used to treat hypopneas, flow limitations EPAP (expiratory positive airway pressure) Always the lower number Maintains upper airway patency Can be used to improve oxygenation (PEEP) Pressure used to treat obstructive apneas Back Up Rate (May or May Not have) A Machine Generated Breath will be delivered at prescribed setting if patient fails to take a breath within a pre-defined timed interval Pressure Support IPAP Minus EPAP Greater Pressure Support=Increased Volume
How it works Green line: Pressure needed throughout breath Red area: Unnecessary pressure delivered Blue line: Delivered pressure CPAP Insp Exp CPAP BiPAP Insp Exp IPAP P FL P OH EPAP P OA One Breath One Breath
Bi-Level/Vent devices Terms to understand Pressure Support IPAP Pressure minus EPAP Pressure The bigger the difference the bigger the volume IPAP 12 cmh20 Pressure Support (12 5 = 7 cmh20) EPAP 5 cmh20
Bi-Level/Vent Devices Additional Terms to Understand Rise Time: The time it takes for the device to reach the IPAP pressure once the breath is triggered IPAP 12 cmh20 Rise Time Micro seconds EPAP 5 cmh20c
Bi-Level/Vent devices Additional Terms to Understand Inspiratory Time: The time spent in the inspiratory phase of the breathing cycle Also known as I- Time or Ti Used on Back up Breaths only unless in Pressure Control Mode IPAP 12 cmh20 Cycle Rise Time Micro seconds Trigger EPAP 5 cmh20c
Why BiPAP therapy? Bi-level Therapy: Simulates a breathing pattern similar to normal respiration Lower pressure on exhalation decreases mask pressure and incidence of leaks Bi-level therapy is initiated because: CPAP titration is ineffective/untolerable (Sleep) Inability to exhale Frequent microarousals Patient feels pressure too high Typically seen in patients at pressures > 13 cm H2O Physician wants to supplement/support the patients breathing (Ventilation) With or Without A Rate (RAD Guidelines) Neuromuscular disorders Advanced COPD Central/Complex Sleep Apnea
Common Bi-Level Names BiPAP S or S/T=Respironics Bilevel Posititve Airway Pressure S=Spontaneous S/T=Spontaneous Timed Auto BiPAP VPAP S or S/T= ResMed Variable Positive Airway Pressure VPAP Auto IntelliPAP Bilevel S
Auto Bi-Level Devices Algorithms are designed to titrate for SLEEP events (not Ventilation) Two Primary Auto Bi-level Machines Philips Respironics DreamStation Auto BiPAP Variable EPAP and IPAP Variable or Fixed Pressure Support ResMed Air Curve 10 Vauto Variable EPAP/IPAP Fixed Pressure Support
Advanced PAP Devices (New School)
Old Technology vs. New Technology 32
Treatment Depends on Underlying Disease Process Servo-Ventilation Devices Primary Goal is to Stabilize an Unstable Breathing Pattern Central/Complex Sleep Apnea Periodic Breathing such as Cheyne-Stokes Respiration Opiod Induced Central Sleep Apnea Bi-level with Volume Assured Pressure Support (AVAPS/iVAPS) Primary Goal is to Assure Adequate Ventilation Central Sleep Apnea Obesity-hypoventilation syndrome (OHS) Advanced COPD Restrictive Disorders Opioid Induced Central Sleep Apnea
Disorders of respiratory rhythm or pattern think Servo-Ventilation Cheyne-Stokes Respiration ( Heart Failure) Not to be used with EF <45% and predominate mod/severe Central Sleep Apnea. Idiopathic central sleep apnea CPAP-emergent central sleep apnea AKA Complex Sleep Apnea Opioid-induced central sleep apnea 34
Central Sleep Apnea 3 main forms of Central Sleep Apnea Idiopathic Central Sleep Apnea Brain issue with control of respiration Periodic breathing Heart failure vs. non heart failure populations Chemoreceptor issue/co 2 issue Pain management patients Complex Sleep Apnea CPAP Emergent events Chemoreceptor issue ~5% may have Central Sleep Apnea (CSA) or Cheyne Stokes Respiration (CSR) Eckert, et al. Chest. 2007; 131:595-607 OSA CSA Complex 35
Central Sleep Apnea Patterns Idiopathic Sleep Apnea Complex Sleep Apnea Periodic Breathing Compl ex ~35 sec 20-40 sec
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Periodic breathing Characteristics: waxing and waning breathing pattern Length is based on disease process causing the breathing pattern Longer events for patients in heart failure 1 (picture A) 60-90 second events of CSR then followed by normal respiration (waxing and waning of respiration) in patients with heart failure 1 Shorter events in those at altitude/neurological disorder/renal failure 1 (picture B) 20 40 seconds on length 1 20-40 sec
Congestive Heart Failure = damaged ventricles Damaged ventricle = decrease cardiac output Cardiac Output of 0.8 LPM = 2.5 second delay to brain Results in Cheyne-Stokes Respiration =Hypoventilation
Why not use BiLevel Therapy with these patients? Exaggerated Tidal Volumes 40
How should we treat these complicated patients? Servo Ventilation: Aim of the SV therapy Stabilize the unstable flow pattern Deliver pressure support only when needed Trigger mandatory breathes when needed Provide efficient pneumatic splint
What is Servo Ventilation? Treatment for complicated breathing patterns such as: Central apnea Complex apnea Periodic breathing such as CSR Provides non-invasive ventilatory support to treat adult patients with OSA and respiratory insufficiency caused by central and/or mixed apneas and periodic breathing. 2 Manufacturers Make Servo Ventilation Devices for Non-Invasive in the US Auto SV advanced Respironics Adapt SV Resmed 42
What do Tom Cruise and Servo Ventilation have in Common?
Servo Ventilation Therapy can stabilize the breathing pattern Stabilized breathing pattern 44
Servo Ventilation: Why it works for the complex patient Obstructive events Unstable breathing or complex breathing e.g. CSR Absence of flow EPAP Auto Pressure Support (PS) Auto Backup Rate Servo Ventilati on Therapy 45
Servo ventilation algorithm Three or Four minutes On a breath-by-breath basis patients Volume/ Peak flow is captured That Volume/ flow is monitored over a moving Three or four-minute window As one breath is added, the initial breath falls off The algorithm establishes a targeted Volume or Flow around that average and is based on the patient s needs (roughly 90-95% of average) 46
Servo ventilation algorithm: decreased flow If: Peak flow/volume falls below target Then: Servo Device increases pressure support 47
Servo Ventilation: Works very well for specific populations of Sleep disordered breathing: Periodic Breathing Complex Sleep Apnea Drug induced Central Sleep Apnea Stabilizes/Pretties up an irregular breathing pattern Not designed for Chronic Respiratory Failure
Why not use auto servo ventilation for a neuromuscular diseased patient? Would continually reset it s baseline, worsening the hypoventilation Normal target continues to decrease continues to under ventilate patient as the night progresses Ventilation Time
Bi-level with Volume Assured Pressure Support (AVAPS/iVAPS)
Patient Selection Decreasing flow, Decreased Effort, Increased Rate Obesity Hypoventilation - COPD ALS - Muscular Dystrophy Head Trauma - Post Polio
Bi-level with Back-up Rate IPAP, EPAP and back up rate are what patient needs at particular time Bi-level with back up rate does not guarantee a delivered tidal volume it guarantees a delivered pressure What happens if the patient s condition worsens? Patient s flow today Patient s flow in 2 months
Respiration changes are also based on sleep stage
Impact of Sleep and COPD COPD patients may have more hypopneas vs. apneas Higher prevalence of insomnia, nightmares and daytime sleepiness Can increase CO2 levels Sleep Is Fragmented with Frequent Arousals and diminished REM Patients with moderate to severe COPD may have a marked response to REM sleep states with dramatic drop in oxygenation Patients may have nocturnal desaturation without having daytime desaturation
Patients prone to Overlap Disease Patients with COPD & Daytime or Nighttime Hypercapnia ( CO 2 ) Moderate to Severe FEV 1 reduction Obese Snorers Wake up with headache after using nocturnal oxygen therapy Flenley DC Clin. Chest. Med. 1985;6(4) :651-661 McNicolas, W. Chest 2000:117:488-538
Bi-level Pressure Delivery Bi-level Devices provide pressure with a variable volume delivery 600 cc 455 cc 450 cc 300 cc V T P 12 cm H 2 O 12 cm H 2 O 12 cm H 2 O 12 cm H 2 O Over time - static pressure therapy with variable volume delivery may not provide adequate therapeutic support for progressive disease states patient conditions: ALS Overlap Syndrome (COPD + OSA) OHS (obesity hypoventilation syndrome)
Amyotrophic Lateral Sclerosis (ALS): Etiology A progressive degenerative disease that affects nerve cells in the brain and the spinal cord When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost voluntary muscle action is progressively lost ALS is often referred to as "Lou Gehrig's Disease"
Etiology and Anatomical Changes Weakened bulbar muscles can cause closing of the airway Nerve and muscle functions relax during sleep causing underventilation complaints of morning headaches, lethargy, and shortness of breath (SOB) Noticed first during REM Sleep BiLevel needs to change with progression of disease Living with ALS: Adapting to Breathing Changes, 1997, ALS Assoc.
Obesity Hypoventilation Syndrome (OHS): Etiology Absence of significant lung or respiratory disease 1 May result from both a defect in the brain's control over breathing and excessive weight against the chest wall makes it hard for a person to take a deep breath inefficient breathing leads to lower PO 2 levels and higher PCO 2 levels in the blood when awake Banerjee, D. and et al. Chest 2007;131;1678-1684 May be referred to as Pickwickian Syndrome
Signs and Symptoms Extreme obesity Often exhibit the following: tired due to sleep loss poor sleep quality chronic hypoxia Difficulty breathing when supine Severe positional hypoventilation/osa OSA plus OHS may cause severe O 2 desaturation during sleep
What if you had a Life Insurance Policy with your Bi-Level Device?
Bi-level with Volume Assurance Automatically adjusts the pressure support level to maintain a consistent Volume IPAP will automatically increase or decrease EPAP maintains an Open Airway
What is Bi-level with Volume Assurance? Acts primarily as a bi-level pressure support device but is able to provide a constant volume. Automatically adjusts the pressure support level to maintain a consistent volume Inspiratory Pressure will automatically increase or decrease to maintain set volume Two Primary Non-Invasive Volume assured Modes in the US AVAPS from Philips Respironics Average Volume Assured Pressure Support Targets Tidal Volume ivaps from Resmed Intelligent Volume-Assured Pressure Support Targets Alveolar Ventilation Used for Both Adults and Some Pediatric Patients
Clinical Benefits of Volume Assurance (insurance) Maintains ventilatory support and tidal volume during progressive ventilatory changes of the patient. Maintains ventilatory support and tidal volume during positional changes during sleep. Provides the assurance of a volume within a bi-level system. Alarms to indicate that volume is not being maintained.
Volume Assurance with PS is NOT recommended for patients with periodic breathing Treatment of periodic breathing requires a variable breath by breath response system so the patients PaCO2 stabilizes quickly Prevents overshooting or undershooting the PaCO2 breath by breath Does not augment the patients tidal volume consistently Volume Assurance with PS does not have a quick variable response to changes in tidal volume. It is designed to adjust and maintain a constant tidal volume with each breath over time. This benefit often seen with patients who have slow declines in their ventilatory conditions.
In Summary: Treating Obstructive Sleep Apnea During Sleep CPAP, Auto CPAP, Bi-Level or Auto Bi-Level Treating ventilatory abnormalities during sleep Disorders of respiratory rhythm or pattern Servo Ventilation Disorders of inadequate level of ventilation (minute ventilation, hypercapnia) Volume Assured Pressure Support 66
Thank You For Your Time Ryan Schmidt, BS, RRT Clinical Specialist Philips Respironics Cell: 402-680-4086 Email: ryan.schmidt@philips.com